Conventional telecommunications chassis and systems associated with gateway devices typically include a host controller and multiple line cards. Highly available systems additionally include a redundant host controller. In such systems, either the primary or the redundant host controller mediates communication between the line cards and shared system resources, such as central storage and external interfaces. Any information flow to or from external devices is conveyed via the active host controller. A line card is unable to communicate with an outside interface except through the active host controller. In addition, when the line cards boot, the operational code of each line card is retrieved from central storage and communicated to the appropriate line card by the active host controller. Since the line cards are not able to directly access shared system resources, the amount of redundancy in conventional prior art systems is limited to the number of host controllers.
In order to achieve increased redundancy and system availability for multi-processor systems, it would be useful if line cards could independently access an external interface even when no host controller is available. In addition, it would be useful if the line cards could independently access other shared system resources.